The invention concerns equipment for compacting trash consisting of packing materials and easily compressed wastes, for instance cardboards, light plastic and wood packaging, paper, wastes from blanks and wood, plastic and metal chips, the compaction taking place in containers open at the top by means of a compacting roller penetrating said container, rotating circularly on the trash and supported from a post reaching above the container, said roller moving relative to the container during the compaction as the filled portion of the container increases.
In a known design of this type, the compacting roller is mounted on the lower end of a feed screw and compacts the trash supplied by this screw, the relative motion between the roller and the trash in the container being implemented by the container or its bottom being raised during compaction.
This arrangement incurs the drawback that only comparatively minor amounts of trash can be compacted by this trash being lifted toward the roller unless the lifting forces be so large that the equipment design becomes uneconomical. Another drawback of the known equipment is that because of its conveyor combination of roller and screw, it is relatively complex, costly and susceptible to malfunction. Furthermore this known equipment is wholly unsuited for bulky trash, which is the case especially for packing materials, as materials of that kind when uncomminuted cannot be seized by the screw.
It is therefore the object of the invention to so design equipment of the initially stated type that it operates with comparatively few parts, in simple and problem-free manner, and is adequate to receive bulky trash.
This problem is solved by the invention in that the arm of the post above the trash container is provided with a vertical shaft comprising at its lower end at least one horizontal support rotatably holding the roller, the roller by its own weight resting on the trash and the arm forming one part of a lift device located on the side of the post and permitting a roller stroke roller due to its own weight, the roller being constrained to perform a continuously alternating forward and backward motion.
This equipment makes it possible to seize and compress trash, in particular also when bulky, in problem-free manner, as the roller impacts the trash by its own weight, the possibility being provided hereby that if the trash is not reduced at once, the roller also can be lifted again from a lower into a higher position, assuring thereby uniform comminution without overloading the machine. A corresponding uniform comminution or reduction is impossible in the known equipment; therein the roller is always guided at the same compression level determined by the lifting device.
The invention offers another advantage over the known equipment in that due to the to-and-fro motion of the roller on the trash, wherein the roller furthermore reverses its direction of rotation after one or several revolutions, the trash will not tangle on the roller. Appropriately the reversal in direction of rotation takes place after one to five revolutions of the roller.
Such a reversal in direction of rotation is already out of the question in the known equipment because the screw can only feed the trash to be reduced in one direction.
The lifting device may consist of a guide device at the free end of the post-arm wherein the vertical shaft is guided in displaceable manner. To that end the shaft can be vertically displaceable by means of a gear rack or a chain drive, so that the lifting motion is effected to install the roller or to remove it. During the compaction the roller anyway and automatically moves upward because of the rising level of the material.
Where the arm of the post is desired to be moved by the lifting device, part of the post can be guided in telescoping manner in a further component.
The roller drive can be mounted within the roller itself, the end of the support holding the roller being rotatably supported with respect to the end of the shaft, making it possible for the roller to circulate.
Another possible drive consists in passing the shaft through an external spatially fixed pipe and to drive it by a motor mounted above the arm of the post or near its upper end, the roller-holding support being solidly joined to the shaft end. In this manner the shaft is made to turn by the external motor, whereby the roller is guided by its beam like an idle wheel over the trash.
Another possibility is to use the rotating shaft to drive a spur or bevel gear unit designed as a miter-gear unit in the vicinity of the roller axis and thereby to drive the roller. This type of drive results in relatively low stresses on shaft and bearings.
In the last cited two cases, the external spatially fixed pipe appropriately performs the lifting motion with respect to the arm of the post.
In lieu of one roller, it is possible also to provide two mutually opposite rollers because thereby a relatively uniform force transmission is achieved into the axis or shaft. In this instance the two rollers can be driven jointly by a bevel or planetary gear unit.
Advantageously the rollers are cylindrical because in that case there is a larger relative speed to the trash in the outer than inner region of the roller. Consequently the roller process trash is turned or twisted with respect to itself and accordingly an advantageous squeezing-through and hence improved compaction takes place.
The vertical shaft can be connected at its upper end by a spur-gear unit to a drive motor which in turn is coupled by a belt drive, preferably a toothed belt which in turn drives a spindle to adjust the height setting of the arm inclusive of the drive units mounted thereon and the roller. The engaging coupling appropriately can be mounted in the belt pulley.
The spindle adjustment controls the roller motion into or out of the container holding the trash.
To that end the spindle is supported in a preferably rectangular cross-sectional spindle pipe to the upper end of which is fixed a spindle nut. In turn the spindle pipe is displaceably guided in a guide carriage displaceable in the vertical post, the lower end of the spindle pipe resting as needed on the base plate or the like of the post.
The guide carriage is provided with guide rollers running in the guide grooves of the post. Appropriately three guide rollers are mounted each time in one cross-sectional plane, two of which engage sideways corresponding grooves of the post while the third guide roller points rearwards and engages a post groove provided there.
Several sets of these guide rollers can be provided along the height of the guide carriage depending on the statics of fastening needs.
It was found advantageous that at least two sets of guide rollers be mounted closer together in the upper section of the guide carriage than in the lower section because it was observed that in operation there is more irregular compression in the lower part of the container than in the upper, whereby additional bracing is required in the lower part. When compressing in the upper part, the sets of guide rollers if called for can also moved upward out of the grooves of the post.
It may be disadvantageous in the lower part of the container, that is when it holds still comparatively little material to be compacted and of a corresponding lesser elasticity, that the full weight of the roller inclusive its drive be resting on this thin stratum of material to be compacted, and therefore the invention further provides at least one spring between the carriage and the post whereby the pressure exerted by the roller in the lower part of the container on the material to be compacted will be decreased.
The spring can be a compression spring mounted between a cantilevered part of the guide carriage and the base of the post. However a tension spring may be very appropriate, which is connected by its upper end to the post and by its lower end to the guide carriage. The tension spring offers the advantage of eliminating the support housing required for a compression spring.
Appropriately the roller is provided on its circumference with teeth of triangular cross-sections engaging the trash to be compacted, these teeth being arrayed along a generatrix of the roller. In a preferred embodiment these teeth assume the shape of a tent-roof with an outwardly pointing tip in the direction of the free roller end face. Thereby jumping between the triangular teeth and the outer wall of the container are avoided, and moreover the teeth are prevented from deeply digging into the trash.
Other tooth shapes are possible provided the above stated criterion of the tooth tips pointing outward toward the free end face be observed.
The same object is met by a convex shape of the roller end face whereby its highest point shall be in the axial region, as in this manner too the trash to be compacted is prevented from jamming between the roller end face and the container inside wall.
In order that the trash at the container center can also be compacted by the roller, the invention furthermore provides a support foot in the region below the vertical shaft, resting on the trash and with a bottom surface located approximately in the same plane as the lowermost generatrix of the roller.
Appropriately the post in the equipment of the invention rests on a forked base plate into which can be inserted a pallet or the like holding the trash.
It is furthermore appropriate to construct the trash-receiving container as a bottomless enclosure provided with forward opening double doors, because the equipment of the invention makes it possible to so compress the trash that it will form a solid bale which can be removed by means of supports onto the pallet.
In order to prevent in that instance that the trash be forced out between the lower edges of this container enclosure and a lower support, for instance a pallet, the invention moreover provides flanges mounted perpendicularly or at a downward slant to the lower edges of the container walls which support the trash being compacted in the region of the lower edges of the said container walls and therefore prevent the trash from being laterally forced out between these lower edges and the support surface.
Appropriately, so it be possible to fill such a container to the upper edge, an upper container part appropriately can be set on this container, said upper part also being equipped with double swing doors so that the trash being compacted shall not be forced out in the last stage of compaction. Accordingly this container upper part also fills a safety function for the operator because preventing undesired access to the operational roller.
Appropriately the container upper part also is open at the top, whereby additional feed of trash is feasible when both container parts being closed.
To cover the spindle towards the container parts, a rail guide is mounted at the guide carriage, the side edges of this rail entering in grooves formed by plate angles of guide means at the container upper part.
The equipment operates as follows:
The lower container part is set by means of a support surface for the trash to be compacted, in particular a pallet between the two prongs of the post, onto the prongs, and then is closed.
Before that, the roller together with its drive had been moved upward by engaging the coupling between the drive motor and the belt drive actuating the spindle, whereby the spindle had been rotated and the spindle pipe had been moved down by the relative motion to its nut.
After the spindle pipe rests on the lower support surface of the post, the spindle in this manner moves the drive and the roller upwards.
Following the closure of the container, the spindle is actuated in the opposite direction and thereby the roller and its drive is lowered into the container, the roller becoming immediately operative because being constantly operationally coupled by the spur-gear unit to the motor.
As the roller keeps on operating, the lower container is gradually filled with more trash, the roller because of its own weight resting on the trash and compressing it, though simultaneously moving upwards. During this operation the spindle drive is disengaged, whereby both the guide carriage and the spindle pipe together with the spindle move upwards at the post when the roller does.
The weight of the roller or the pressure exerted by it is decreased in the manner already described by the spring mounted in the lower region of compression.
When the trash and hence the roller arrive at the upper edge of the lower container part, the spindle is actuated by engaging the spindle-drive coupling, whereby the roller is lifted off the trash and the entire drive inclusive of the upper container part is moved upwards.